I tried the next step formula once, but then went back to regular. He will get regular formula until he is ready to move on to other milk.
We weaned around 8 1/2 months because my supply was not satisfying Reid. I was missing pumping sessions at work and couldn't sustain it anymore

We had a seamless transition to formula. I would mix some formula in with a bottle of BM and he never seemed to notice when we went to full on formula.